62 xiif; Ruur. 



eotmtry. * i'Thits, the cocoa, and the cashew-nut, and the seeds of tlie mahog-anj-, 

 have heen kno'\\'n to perfonn long Toyages, without injuiy to their vitality. Squii-- 

 rels, laying up their winter stores in the earth, bii-ds, migi-ating from clime to 

 clime, and from island to island, in like manner conspire to effect the same im- 

 portant end. \ 



CHAPTER X, 



THE BOOT. 



136. The root/is the basis of the plant, and the principal 

 source of its nourishment. It originates with the radicle of the 

 seed ; the tendency of its gi-owth is downwards, and it is gener- 

 ahy immersed in the soil.'i 



a. When tlie radicle has burst the integuments of the seed, and peneti-ated th® 

 soil,/ its body becomes divided into brandies, or fibres; each of these is agaiia 

 divided and sub-divided into fibres, often exceedingly numerous and minute, ever 

 extending and raultijilying, until the vegetable has attained its full growthi 



137. The prone direction of the root is accounted for/by the extreme delicacy 

 of the fibres, which renders them averse to the air and fight, by their avidity fo? 

 moistiu-e, and by the ellects of gravitatioiii 



a. iUthough the primary direction of'^ the roots is downward^' tliey are not 

 kno^vn to extend to any great depth, iifter having descended to a certain dis- 

 tance beneath the surface, they extend themselves horizontally, keeping at about a 

 uniform depth, however great the in-egularities of the smface.' 



138. The number and extent of the roots/must alwftys correspond to the 

 demands of the vegetable, both for affording it nourishment, and for maintaining 

 it in its erect position. It follows, therefore, that for every expanding leaf, or 

 extending twig, there must be a conesponding increment of the roots and fibres 

 beneath the soil.^ 



139. Roots are generally distingitished from sterns^ "by their 

 downward dhection, by the presence of absorbing fibres, by the 

 constantly irregular arrangement of their branches, and by the 

 absence of buds, stomata, and pitliA 



140. To all these characteristics there are, however, exceptions. -^ Thus, buds, in 

 peculiar cu-cumstancos, are developed by the roots, sending up shoots, or suckers, 

 around the parent stem: j This does not happen in the natural or healthy state 

 of the plant,,-but only when the life of the iipper axis is partially or wholly 

 destroyed, the roots remaining in full vigor, and elaborating more uouiisliment 



